short question

[arkain101]

What is the maximum time dialtion that can happen.

According to the equations, if you were to travel C, or super close to it. At what, umm ratio, would the time around you move at? I was wondering because if it makes time go super fast around you, then the universe could die out because your time would stop, and the surrounding time should move almost infinite forwards, or really fast anyway.

Another question,

So I was thinking if you were to fly in a ship at .9C to attempt to travel into time like we think we can. The earth and planets would begin to revolove around the sun extremely fast from the ships view. So wouldnt this tell the ship traveler that earth was going somewhere close to .9C or past C?

Cause I was thinking, when we see something fly by really fast near C, its time looks slow, but it is moving super fast!! and according to the "something" flying really fast, it will feel at rest too and the earth for example would be taking on the same perspective in the sense that it was moving really fast?

Its like Object A going fast makes its view of things around it going fast and it going slow, and the object b going slow sees object A going fast. So, I see some kind of equalibrium going on here..
You see something go fast and its time is slow, the something going fast sees you going faster. So its there is not only the twin paradox problem, what about the velocity comparison problem I am mentioning here.

it turned out as longer question than expected.

[CraigD]

Originally Posted by arkain101

What is the maximum time dialtion that can happen.

The maximum time dilation that could occur is determined by several factors. One is how effectively an object such as a spacecraft can be protected against collision with debris in the region of space it is traversing. Another is how much energy is available to accelerate the object – ultimately, even with perfect conversion of matter to energy, and all other engineering problems solved, only a finite amount of mass-energy is available in a particular volume of space for use in accelerating an object

According to the equations, if you were to travel C, or super close to it. At what, umm ratio, would the time around you move at? I was wondering because if it makes time go super fast around you, then the universe could die out because your time would stop, and the surrounding time should move almost infinite forwards, or really fast anyway.

In principle, and subject to the limitations outlined above, this is possible. Such a scenario is the subject of the late Poul Anderson’s 1970 science fiction classic,

”Tau Zero”
”Tau Zero”

. “Tau” is the symbol traditionally used to represent the quantity (1-(v/c)^2)^.5, which approaches zero as v approaches the speed of light, c.

So I was thinking if you were to fly in a ship at .9C …

I believe the gist of what you’re asking is: “doesn’t an observer on a ship traveling nearly the speed of light passing close to a planet see events on the planet happening at an accelerated rate, while an observer on the planet sees events on the ship happening at an accelerated rate?”

The answer is “yes”. At .9 c, the time dilation factor would be (1-(.9**2))**-.5 =~ 2.3 – quite noticeable, if not extreme. This raises the question “which observer gets older in the twins paradox?” (which isn’t really a paradox – it’s just traditionally called one) The answer to this is somewhat complicated, but amounts to “which observer does the accelerating?”, and the fact that, to have a high relative velocity for a long time, one must travel a long distance.

I hope these answers are helpful.

[kamil]

Originally Posted by arkain101

So I was thinking if you were to fly in a ship at .9C to attempt to travel into time like we think we can. The earth and planets would begin to revolove around the sun extremely fast from the ships view. So wouldnt this tell the ship traveler that earth was going somewhere close to .9C or past C?

This is self contradictory, if A moves past B at 0.9C, then B moves past A at 0.9C.


The whole confusion here comes form you thinking that time dilation has an affect on observed speed. It doesnt! Length Contraction makes up for it:

A goes past B at 0.5c. B observes 0.5c=l/t A observes v=l'/t'

l'=l/gamma t'=t/gamma

v=(l/gamma)/(t/gamma)
v=l/t
Therefore: v=0.5c

So length contraction makes up for the affects of time dilation.

That is where length contraction comes from, from the fact that v=v' where
t does not equal t'.

[arkain101]

thank you guys for the responses.

I seem to have a handle on the concepts you have given.

I am concirning somewhat different and new ideas here.

According to the equations, if you were to travel C, or super close to it. At what, umm ratio, would the time around you move at? I was wondering because if it makes time go super fast around you, then the universe could die out because your time would stop, and the surrounding time should move almost infinite forwards, or really fast anyway.

In principle, and subject to the limitations outlined above, this is possible. Such a scenario is the subject of the late Poul Anderson’s 1970 science fiction classic, ”Tau Zero”. “Tau” is the symbol traditionally used to represent the quantity (1-(v/c)^2)^.5, which approaches zero as v approaches the speed of light, c.

Going from here. While length contraction makes up for cirtain aspects. But say a ship is flying either back into the solar system or sort of far away along past it at a significant enough velocity to cause time to be going alot faster in the region of the solar system. Since the clocks would look fast on earth, the earth would logically be revolving around the sun in the range of the same time dialation. This not a direct comparison like seeting something fly by. If time can fluctuate (and have a scenarious like I mentioned ealier about the universe experiencing extreme forward time and maybe having something drastic like it being died out by the time you get your ship stopped, hypothetically of course) then it would be visible to see earth rotating around the sun in a much faster rate? if you were to be traversing in space near the solar system at significant speed to create visible time dialation in your surroundings.

A planet revolving around a star, compared to just viewing a passing by object would seem to be quite a different set of scenarios. Considering that a revolving planet is not just drifting by, but the viewing of cycles around its start should likeswise speed up.